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Can a polyhedron have for its faces (i) ...

Can a polyhedron have for its faces (i) 3 triangles? (ii) 4 triangles? (iii) A square and four triangles?

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In order to solve this problem use the definition of polyhedron and visualize if it is possible to create a shape with the help of given figures.
A solid figure consists of four or more plane faces (all polygons), pairs of which meet along an edge, three or more edges meeting at a vertex.
Answer:
Polyhedron: A three-dimensional figure whose faces are all polygons. A polyhedron has to have a minimum of four faces.(i) No, a polyhedron cannot have 3 triangles for its faces. Because a polyhedron must have edge meetings at vertices which are points.(i) No, a polyhedron cannot have 3 triangles for its faces. Because a polyhedron must have edge meetings at vertices which are points.(iii) Yes, a polyhedron has its faces a square and four triangles which makes a pyramid on a square base. Because all the eight edges meet at the vertices.Hence, a polyhedron can be made from '4' triangles and a square and four triangles. But it cannot be made from '3' triangles.
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